Gas turbine systems are widely utilized in fields such as power generation. A conventional gas turbine system includes a compressor, a combustor, and a turbine. The compressor supplies compressed air to the combustor, wherein the compressed air is mixed with fuel and burned, generating a hot gas. This hot gas is supplied to the turbine, wherein energy is extracted from the hot gas to produce work.
During operation of the gas turbine system, various components and areas in the system are subjected to high temperature flows, which can cause the components and areas to fail. Since higher temperature flows generally result in increased performance, efficiency, and power output of the gas turbine system and are thus desired in the gas turbine system, the components and areas that are subjected to high temperature flows must be cooled to allow the gas turbine system to operate with flows at increased temperatures.
Examples of areas that should be cooled are the wheel space of the turbine section, which is the area of the turbine section surrounding the turbine rotor wheels, and the rotor joint, which is the joint between the compressor rotor and turbine rotor. For example, as the temperature in the wheel space increases due to increased temperature of flows through the wheel space or due to increased ambient temperatures external to the gas turbine system, components in the wheel space, such as rotor and bucket assembly components, may be subject to thermal expansion. This thermal expansion may eventually cause the various components to rub or otherwise contact each other, or may create excessive stresses in the components, potentially resulting in catastrophic damage to the components and to the gas turbine system. The rotor joint may similarly experience increased temperatures due to increased flow temperatures and/or ambient temperatures, and may thus be a life-limiting component of the system.
Various strategies are known in the art for cooling the wheel space and rotor joint to prevent damage to the gas turbine system. For example, many prior art strategies utilize inducers to flow a portion of the air from the compressor to cool the wheel space and rotor joint. The inducers accelerate the compressor discharge air flowing therethrough, reducing the temperature of the air before the air enters the wheel space and/or interacts with the rotor joint.
Typical prior art inducers are expensive, complicated devices. For example, many prior art inducers are cast into various portions of the gas turbine system between the compressor and the turbine, and include multiple layers of structure for accelerating air flows therethrough. These prior inducers have a variety of disadvantages. For example, as mentioned, the inducers may be expensive and complicated to manufacture. Additionally, because typical prior art inducers are cast, the inducers are not modifiable or tunable during system testing, validation, or commissioning, and the various components of the inducers are not easily repairable.
Thus, an improved inducer for a gas turbine system would be desired in the art. For example, an inducer that is relatively affordable and simple to manufacture and install in a gas turbine system would be desired. Additionally, an inducer that includes features that are modifiable or tunable, and that may further be easily repairable, would be advantageous.